The correct answer is A. fluorosis.
Fluoride is a naturally occurring mineral that is found in water, soil, and rocks. It is also added to some toothpastes and mouthwashes. Fluoride can be beneficial to teeth by helping to prevent cavities. However, too much fluoride can cause fluorosis, a condition that can discolor and weaken teeth.
Chlorosis is a plant disease that is caused by a lack of chlorophyll. Chlorophyll is a green pigment that is essential for photosynthesis. Chlorosis can cause leaves to turn yellow or white.
Minamata disease is a neurological disorder that is caused by mercury poisoning. Mercury is a heavy metal that can be found in fish and shellfish. Minamata disease can cause symptoms such as numbness, tingling, and weakness.
Methemoglobinemia is a condition that is caused by a lack of oxygen in the blood. Methemoglobin is a form of hemoglobin that cannot carry oxygen. Methemoglobinemia can cause symptoms such as cyanosis (blue skin), shortness of breath, and seizures.